Persistent delays in integrating the indigenously developed Air Independent Propulsion (AIP) system have continued to hamper India’s plans to upgrade its Scorpene-class submarines, with the Defence Research and Development Organisation’s AIP still not operationally ready as of August 4, 2025. The first Scorpene, INS Kalvari, completed its recent refit without the AIP upgrade, shifting hopes to the next vessel, INS Khanderi, scheduled for refit in mid-2026. An agreement for AIP integration between Mazagon Docks and the French Naval Group was only finalized on July 23, 2025. The repeated delays, originally compounding since a missed 2017 deadline, have raised concerns, especially as Pakistan is set to induct eight AIP-equipped submarines from China, intensifying regional maritime competition.